Frequently Asked Questions
How do I install a carbon filter on my air cleaner?
You must remove the plastic cover from the activated carbon filter and install in the unit. Position the pre-filter in the rear of the unit (closest to the electronic cell) and the carbon filter on the front side where the air comes out. Make sure the electronic cell is properly placed in the cabinet - the airflow arrow on the end plate should be pointing toward the fan. Electronic air cleaners should not be placed in any area where potentially explosive gases or vapors exist. In addition, they should not be used in wet environments.

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• What is the difference between the Friedrich C-90B and the Friedrich C-90A?

• Why does the light on my C-90 blink or flicker?

• Is the C-90B effective against mold?

• Does the C-90B electronic air cleaner produce any ozone?

• How can I buy replacement carbon filters?

• How often should I replace my carbon filter?

• Do I need to replace my pre-filter?

• Where do I get filters for my C-90A or C-90?

• How do I find a Friedrich dealer in my area?

• Where can I download an Owner's Manual?

• What are the Friedrich C-90B's dimensions?

• How often should I replace the carbon filter in my Friedrich air cleaner?

• How quiet is the Friedrich C-90B?

• Aren't the filters really expensive?

• How large an area will the Friedrich C-90B handle?

• Will the Friedrich C-90B discolor walls, drapes or furniture?

• How do I know which air cleaners are really effective?

• How much electricity does the Friedrich C-90B air cleaner require?

• How do I clean my Friedrich air cleaner?

• How do I install a carbon filter on my electronic air cleaner?

• Can I use my Friedrich C-90B with my window open?

• Why is my electronic air cleaner making a popping sound?

• Are there discounts for purchasing more than one Friedrich C-90B?